1. Field of the Invention
The present invention relates to an endoscope system that is used during surgery to resect a tumor, such as cancer, or before the surgery.
2. Description of the Related Art
In recent years, laparoscopic surgery to perform an operation using a laparoscope has been drawing attention. In the laparoscopic surgery, a laparoscope and surgical treatment tools are inserted into an abdominal cavity through two or three trocars provided in the abdomen of the patient, and the abdominal cavity is inflated with pneumoperitoneum gas made of carbon dioxide. Then, the operator performs various operations using the surgical treatment tools while observing an image of the abdominal cavity displayed on the monitor. Thus, for the laparoscopic surgery, it is necessary to perform operations in the limited field of view of the laparoscope. Accordingly, a high level of skill is required for the operator. However, since there is no need for laparotomy, unlike in general surgery, the burden on the patient is considerably reduced. When performing such laparoscopic surgery, the oxygen saturation of a region of interest is monitored using an oxygen saturation monitoring device (for example, refer to JP1993-49624A (JP-H05-49624A)), such as a pulse oximeter, so that the tissue in the region of interest does not fall into a low oxygen state.